Tuesday, 30 April 2013

Trainwreck Amplifiers - Express - Liverpool - Rocket

Ken Fischer with his Trainwreck amps
If you're interested in guitar amplifiers and haven't heard of Trainwreck amps then you must be stuck on a desert island. Known for their no frills design, great clean shimmer and screaming lead tones Trainwreck amplifiers were hand made in the 80s and through the 90s by the late Ken Fischer. He was one of the first "boutique" amplifier manufacturers to enter the market and many of his design philosophies, construction techniques and circuit designs are still around in the amplifier market today.

An unbelievable collection of Trainwreck and Vox amplifiers
There are three main Trainwreck designs;
  •  the "Express", a 50W screaming lead machine using 2 EL34 output valves to generate super compressed lead guitar tones.
  • the "Liverpool", a 30W combination of the Express preamp alongside a quad of EL84 output valves to create a slightly mellower version of the Express. Ken designed this one with single coil guitars in mind.
  • the "Rocket", a super fine tuned version of the VOX AC30 Top Boost.
Unfortunately Ken only managed to produce around 100 or so amplifiers before his health deteriorated to the point where he was unable to build - this makes original Trainwrecks rarer than hens teeth (or in fact rarer than original Lovepedal circuit designs ;).


Now, before we go any further and take a look at the actual circuits we should probably have a listen. Here's some demo videos of the Trainwreck amplifiers in action;




So there they are, some pretty decent sounding amplifiers. But we want to know how to build them. There are literally thousands of forum posts and discussion on these amplifiers and a few kind owners of originals have taken pictures of their amps to allow others to attempt to clone there sound. Most of this information is stored on the great Tube Amp Garage Forum (which also covers the much sought after Dumble amplifiers).

A 1989 Trainwreck Express
"Ingrid" Trainwreck Express
Gutshot of Ingrid
Now, first up is the Trainwreck Rocket schematic;



The Trainwreck Liverpool Schematic;



And finally the Trainwreck Express Schematic;



Notice the similarities between the Liverpool and the Express - same preamp circuit different power amp. Also notice how they use that third triode "cold biased" to get some real preamp clipping going in much the same way as the great Marshall JCM800 (2204) does. The Rocket, as you can see, is just the top boost Vox AC30 refined to a single channel.

On their own the circuits are nothing spectacular; the key with these amplifiers is in their construction and tube selection (and transformer selection - the Express uses a custom build output transformer with a 6k6 primary and the Liverpool a, rather odd, 5k2 primary (usually quad el84 amps use an output transformer with a 4k primary winding)) - if you don't get these factors correct then you'll have an amp that sounds all right, but it won't sound like a Trainwreck. But how do you select tubes for Trainwrecks and tweak them to perfection? Well, it's back to reading all those forum posts and filtering out the truth from the myth and being prepared to lay out some serious cash on NOS tubes!

Below are the links for a full BOM (Bill of Materials) and Layout files for each of the Trainwreck amps.

For a full schematic, BOM and layout of the Express check out this Amp Garage topic; http://ampgarage.com/forum/viewtopic.php?t=5691

For the Liverpool check out this topic; http://ampgarage.com/forum/viewtopic.php?t=5677

And for the full Trainwreck Rocket documents have a look here; http://ampgarage.com/forum/viewtopic.php?t=5684

Tuesday, 2 April 2013

Vemuram - Jan Ray Overdrive


So, if you've heard of the Japanese pedal company Vemuram you've probably heard about this: Vemuram Jan Ray = Timmy Clone. It's an attractive pedal - nice brass enclosure, vintage looking knobs. Check it out in action here against the Timmy (yes, there are slight differences - the treble control has a different range and the OPAMP chip is different but the circuit structure is exactly the same.);


Now, the Timmy (the original which is made by Paul C and has been since 1997) has been cloned several times in the past by many different manufacturers. Off the top of my head there's the Danelectro Cool Cat Transparent Overdrive and the Lovepedal OD11.

Well we have mmolteratx to thank for discovering this latest example of boutiquer cloning. He picked one up and gutted it before tracing it out and providing a schematic for us;

Vemuram Jan Ray Guts
Vemuram Jan Ray Guts
And here's the schematic he drew up;


Yeah, it's a Timmy with a slightly altered treble control. Here's an explanation from mmolteratx;

"No, it's entirely in the different treble control. The bass response is exactly the same, all the trimmer does is vary the effective value of R4, which sets the gain of the stage. The treble control on the Jan Ray lops off everything above 2.8kHz at -6dB/decade at max. The Timmy's control at minimum does the same, but at 10.6kHz. Just use the Timmy's control in a different range and you've got a Jan Ray."

So, there you have it, nothing new and yet another clone. For more information, and a great layout from IVIark (of tagboardeffects.blogspot.com) on the Vermuram Jan Ray Overdrive visit this; http://freestompboxes.org/viewtopic.php?f=7&t=21934